Silyl-functional fumarates as well as maleates are well known in the art. There are many literature sources describing their preparation and uses.
The most common preparation of these materials is to react, in the presence of a catalyst, a maleate or fumarate containing an unsaturated hydrocarbon on the end or ends of the molecule with a hydrogen halogensilane or alkoxysilane. These reactions are often difficult and ineffective. The handling of toxic chemicals is required in some of them, platinum catalysts are used, and the raw materials may not be readily available and complex to produce.
Mitchell, U.S. Pat. No. 4,281,145 produces silyl functional maleates and fumarates by reacting a hydrogen chlorosilane with an olefinic maleate or fumarate in the presence of platinum. The resulting silyl-functional maleate or fumarate is then reacted with an alcohol to provide the desired alkoxy functionality. This process requires the difficult addition reaction step and the use of a platinum catalyst, however, it has eliminated the handling of toxic starting materials. It is also preferred that in Mitchell the addition reaction be carried out in the presence of an organic solvent.
Berger et. al., U.S. Pat. No. 3,759,968 is a less efficient method similar to that taught by Mitchell. Berger et al provides further detail to show the complexity of producing the starting materials necessary for the disclosed method.
Berger et. al., U.S. Pat. No. 3,773,817 teaches a method in which an hydrogenalkoxysilane is reacted in the presence of platinum with an olefinic maleate to produce the silyl-functional maleate. However the desired starting hydrogenalkoxysilane is hydrogentrimethoxysilane which is known in the art to be highly toxic. Also this reaction results in low yields of product.
The reaction mechanisms taught by prior art make it impossible and unobvious to produce silyl-functional fumarates or maleates in which there is less than 2 carbons joining the silicon molecule to the fumarate or maleate joining the silicon molecule to the fumarate or maleate group. The is due to the necessity of having a C.dbd.C bond on the maleate or fumarate for addition to the silane.
It is an object of this invention to present a method for production of silyl-functional fumarates that does not require addition across a double bond, the use of platinum or the handling of toxic starting materials.
It is further an object to present novel silyl-functional fumarates that are prepared by this method.
It is further an object of this invention to provide a method of adhering polyolefins to various substrates using silyl-functional fumarates.